Coefficient of Thermal Expansion Data

A Coefficient of Thermal Expansion, typically represented by the symbol , is a measure of the change in length of a material in response to a change in its temperature.

Within small temperature changes, the change in the length of a material is proportional to its change in temperature. Materials expand as temperatures increase, and contract with decreasing temperatures. Different materials expand by different amounts as shown in the table below.

The data shows thermal expansion material properties that correspond with an approximate temperature of 20 degrees Centigrade (68 degrees Fahrenheit). A material's Thermal Expansion Coefficient is not a fixed constant... the Coefficient value itself also increases (slightly) with higher temperatures.

All data should be considered as approximate as values can vary widely between individual material specimens depending on several factors including alloy type and heat treatment.